The bank is expanding in a revamped building that has gone from being one of the city’s homeliest to a gleaming structure

J.P. Morgan Chase & Co. is more than tripling its office space on Midtown Manhattan’s far West Side in a revamped building that has gone from being one of the city’s homeliest to a gleaming structure with all the features in vogue among media and tech companies.

The bank has closed on a 15-year lease deal for about 300,000 square feet at Five Manhattan West, expanding office space for its digital teams from 125,000 square feet...